Procedures involved in compiling the road data include (1) obtaining 1 meter digital imagery and ancillary data for collecting, interpreting, and classifying the road features, (2) compiling the Digital Line Graph (DLG) vector data by 1:24,000-scale USGS quadrangle tiles, (3) merging the 1:24,000-scale quadrangle tiles into one seamless data set, and (4) translating and reattributing the features into user-friendly data sets. The translated attribution is described below in the Supplemental_Information section.
Base cartographic layers are part of the USGS FRIR project cooperative effort to provide qualitative and quantitative information about infrastructure (aggregate, energy, water, habitat) features needed by growing urban regions like the Denver metropolitan area. The objective of the project is to develop GIS information about water and other themes in such a way that decision makers can use this information to make land use planning decisions, growth models and will be used by the project scientists for multiple studies of the changing landscape of the Front Range and the impact on various resources.
In addition to roads, the USGS has created six other base cartographic layers consisting of: hydrography (FRIHY), miscellaneous transportation (FRIMT), railroads (FRIRR), manmade structures (FRIMS), public land survey system (FRIPL), and boundaries (FRIBD). FRIRD contains line attributed features. The data layers are available at (<URL:http://rockyweb.cr.usgs.gov/frontrange/datasets.htm>)
Field Definitions:
CAT Theme Category
PIC Primary Identification Code
DSC Descriptive Code
WID Road Width
LABEL Feature Definition
INTERSTATE Interstate Highway Route Number
US U. S. Highway Route Number
STATE State Highway Route Number
MATT Redefined PIC, DSC, and WID Codes into one field
SAMPLE .AAT INFO FILE:
CAT =17 road category
PIC =209 class 3 street
DSC =602 overpassing, on bridge
WID =999 road width in feet
** REDEFINED ITEMS ** combination of PIC, DSC, and WID
MATT =209760999
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!! ATTENTION !!
NEATLINE: designated by PIC and DSC codes of 777
NULL VALUES: '9's are used to fill blank fields
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** PIC codes for NODES: none
** PIC codes for POLYGON features: none
** PIC codes for LINE attributes:
PIC Definition
201 primary route, class 1, symbol undivided
202 primary route, class 1, symbol divided by centerline
203 primary route, class 1, divided, lanes separated
204 primary route, class 1, one way, other than divided
205 secondary route, class 2, symbol undivided highway
206 secondary route, class 2, divided by centerline
207 secondary route, class 2, divided, lanes separated
208 secondary route, class 2, one way, other than divided highway
209 road or street, class 3
210 road or street, class 4
211 trail, class 5, other than four-wheel-drive vehicle
212 trail, class 5, four-wheel drive vehicle
213 footbridge
217 road or street, class 3, divided by centerline
218 road or street, class 3, divided, lanes separated
223 road in service facility or rest area
401 traffic circle
402 cloverleaf or interchange
403 tollgate, toll plaza, or perimeter of toll plaza
732 traffic circle, class 3
** DSC codes: descriptive code for PIC codes:
DSC Definition
601 in tunnel
602 overpassing, on bridge
603 under construction, known classification
605 labeled "old railroad grade"
607 underpassing
** WID codes: width in mils of feature to scale (at 1:24,000)
WID Definition WID Definition
650 46-55 feet; 0.025 inches 651 56-65 feet; 0.030 inches
652 66-75 feet; 0.035 inches 653 76-85 feet; 0.040 inches
654 86-95 feet; 0.045 inches 655 96-105 feet; 0.050 inches
656 106-115 feet; 0.055 inches
** Route Numbers
INTERSTATE Interstate Highway Route Number
US U. S. Highway Route Number
STATE State Highway Route Number
The data was collected for government use and represents the results of data collection for a specific activity. USGS makes no representation as to the suitability or accuracy of the data for any other purpose and disclaims any liability for errors that the data may contain. As such, it is only valid for its intended use, content, time, and accuracy specifications. While there are no explicit constraints on the use of the data, please exercise appropriate and professional judgment in the use and interpretation of this data.
Acknowledgment of the U.S. Geological Survey would be appreciated for products derived from this data.
See Entity_and_Attribute_Information and Supplemental_Information sections.
See capture conditions in Part 2-:Standards for Digital Line Graphs and at (<URL:http://rockyweb.cr.usgs.gov/nmpstds/dlgstds.html>)
See Supplemental_Information section for item definitions.
FRIRD.AAT:
COLUMN ITEM NAME WIDTH OUTPUT TYPE N.DEC ALTERNATE NAME
1 FNODE# 4 5 B -
5 TNODE# 4 5 B -
9 LPOLY# 4 5 B -
13 RPOLY# 4 5 B -
17 LENGTH 8 18 F 5
25 FRIRD# 4 5 B -
29 FRIRD-ID 4 5 B -
33 CAT 2 2 I -
35 PIC 3 3 I -
38 DSC 3 3 I -
41 WID 3 3 I -
44 LABEL 50 50 C -
94 INTERSTATE 20 20 C -
114 US 20 20 C -
134 STATE 20 20 C -
** REDEFINED ITEMS **
35 MATT 9 9 I -
CAT Theme Category (DLG Roads = 170) PIC Primary Identification Code DSC Descriptive Code WID Road Width LABEL Feature Definition INTERSTATE Interstate Highway Route Number US U. S. Highway Route Number STATE State Highway Route Number MATT Redefined PIC, DSC, and WID Codes into one field
The act of distribution shall not constitute any such warranty, and no responsibility is assumed by the U.S. Geological Survey in the use of this data, software, or related materials.